2016 BMW 320i F30 - P2096 Post Catalyst Fuel Trim System Too Lean error > Need advice [Archive] - Bimmerforums

bourmb

12-30-2021, 04:35 PM

I have an intermittent Check Engine Soon orange light that comes and goes by itself that's tied to a permanent code P2096 error (Post Catalyst Fuel Trim System Too Lean). I would like to troubleshoot the issue versus taking it to a non-BMW service repair shop if I don't have to. The car currently has 76,000 miles on it and has been flawless with the exception of a failed right high beam in the right light module (halogen beam) which I know is not a bulb failure. We bought the car with 45,000 miles which I have to assume the car still has the original spark plugs in it, too. I've done some digging and it appears this code could be an upstream O2 sensor failing or a vacuum leak. I have verified the airbox is shut and sealed properly, too. To my knowledge the car drives fine and it appears no additional soot is emitted from the exhaust pipe.

I used my OBDII sensor and snapped some screenshots from the Auto Doctor app for the Bank 1 - Sensor 2 Output Voltage and Current. Can someone tell me if these graphs look normal? These photos were taken after the car was operating for about 10 minutes. I hate to spend $150 on a Bosch O2 sensor just to find out it's not the issue. Hence, the reason why I'm asking the question in this forum. I appreciate all input. Attached is the Google Photos link to various screenshots I took of my phone app regarding O2 sensor voltage and amp readings. Is it normal for the voltage to fluctuate so much?

https://photos.app.*******/SyZgtcvi4zrebVcn8

328 Power 04

12-31-2021, 10:05 AM

Picture link didn't come through correctly.

This car would greatly benefit with a scan from a tool that can read BMW manufacturer codes. P codes can be vague and not always report everything. Being able to see live parameters is good, at least.
If you're using apps, check out Bimmerlink.

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If this code is true and the precat sensor isn't reporting too lean, then unless there's a hole in your exhaust, the O2 sensor is potentially bad.